The invention is particularly useful for the protection of flow directed catheters used in the measurement of central venous pressure and pulmonary wedge pressure during and after cardio-pulmonary bypass surgical procedures.
In these procedures, the patient is monitored using a pulmonary artery balloon tipped catheter having at least two lumens. The catheter is placed percutaneously before induction of anesthesia. In certain instances it has been observed that the balloon of the catheter will fail to wedge after cardio-pulmonary bypass and the catheter has to be repositioned. Manipulation of the catheter to reposition it is recognized to be hazardous because over a period of time exposed segments of the catheter may have become contaminated and introduction of this exposed portion may cause infection.
In accordance with prior art practice for the insertion of the catheter, a vein such as the right internal jugular vein of the patient is entered with a hollow needle over which a teflon radio-opaque catheter may be placed. If the radio-opaque catheter is used the needle is removed and a stainless steel wire guide is then introduced through the catheter into the lumen of the vein. After removal of the catheter, an introducer device is passed over the guide through a small incision into the lumen of the vein. The wire guide is then removed and the flow directed catheter inserted and positioned through the introducer device. Known practice also involves the use of a plastic sheath which is tied or otherwise secured at one end to the introducer. After the catheter has been completely advanced to the wedge position, the opposite end of the sheath is fully extended over the catheter to a position remote from the introducer. This end is then fastened in place by a sterile fastening so that a length of catheter between the introducer and the opposite end of the sheath is maintained in sterile condition. This length, which may be as long as 25 in., can be advanced easily into the vein if the catheter again has to be moved to the wedge position after dislodgement or migration.
The present invention relates to improvements in method and apparatus of catheter placement and protection by providing a disconnectible guide tube means within a flexible sheath for ease of feeding a catheter through the assembly comprising the plastic sheath extending between front and rear hubs particularly when used with an adapter with side port and catheter introducer.